Cilofexor in Patients with Compensated Cirrhosis Due to Primary Sclerosing Cholangitis: an Open-label Phase 1B Study.

OBJECTIVES: This proof-of-concept, open-label phase 1b study evaluated the safety and efficacy of cilofexor, a potent selective farnesoid X receptor agonist, in patients with compensated cirrhosis due to primary sclerosing cholangitis (PSC). METHODS: Escalating doses of cilofexor (30 mg [weeks 1-4], 60 mg [weeks 5-8], 100 mg [weeks 9-12]) were administered orally once daily over 12 weeks. The primary endpoint was safety. Exploratory measures included cholestasis and fibrosis markers, and pharmacodynamic biomarkers of bile acid homeostasis. RESULTS: Eleven patients were enrolled (median age: 48 years; 55% men). The most common treatment-emergent adverse events (TEAEs) were pruritus (8/11 [72.7%]), fatigue, headache, nausea, and upper respiratory tract infection (2/11 [18.2%] each). Seven patients experienced a pruritus TEAE (one grade 3) considered drug related. One patient temporarily discontinued cilofexor owing to peripheral edema. There were no deaths, serious TEAEs, or TEAEs leading to permanent discontinuation. Median changes (interquartile ranges) from baseline to week 12 (predose, fasting) were -24.8% (-35.7, -7.4) for alanine transaminase, -13.0% (-21.9, -8.6) for alkaline phosphatase, -43.5% (-52.1, -30.8) for gamma-glutamyl transferase, -12.7% (-25.0, 0.0) for total bilirubin, and -21.2% (-40.0, 0.0) for direct bilirubin. Least-squares mean percentage change (95% confidence interval) from baseline to week 12 at trough was -55.3% (-70.8, -31.6) for C4 and -60.5% (-81.8, -14.2) for cholic acid. Fasting fibroblast growth factor 19 levels transiently increased after cilofexor administration. CONCLUSIONS: Escalating doses of cilofexor over 12 weeks were well tolerated and improved cholestasis markers in patients with compensated cirrhosis due to PSC (NCT04060147).

High burden of viruses and bacterial pathobionts drives heightened nasal innate immunity in children.

Studies during the COVID-19 pandemic showed that children had heightened nasal innate immune responses compared with adults. To evaluate the role of nasal viruses and bacteria in driving these responses, we performed cytokine profiling and comprehensive, symptom-agnostic testing for respiratory viruses and bacterial pathobionts in nasopharyngeal samples from children tested for SARS-CoV-2 in 2021-22 (n = 467). Respiratory viruses and/or pathobionts were highly prevalent (82% of symptomatic and 30% asymptomatic children; 90 and 49% for children <5 years). Virus detection and load correlated with the nasal interferon response biomarker CXCL10, and the previously reported discrepancy between SARS-CoV-2 viral load and nasal interferon response was explained by viral coinfections. Bacterial pathobionts correlated with a distinct proinflammatory response with elevated IL-1ß and TNF but not CXCL10. Furthermore, paired samples from healthy 1-year-olds collected 1-2 wk apart revealed frequent respiratory virus acquisition or clearance, with mucosal immunophenotype changing in parallel. These findings reveal that frequent, dynamic host-pathogen interactions drive nasal innate immune activation in children.

Considerations for viral co-infection studies in human populations.

When respiratory viruses co-circulate in a population, individuals may be infected with multiple pathogens and experience possible virus-virus interactions, where concurrent or recent prior infection with one virus affects the infection process of another virus. While experimental studies have provided convincing evidence for within-host mechanisms of virus-virus interactions, evaluating evidence for viral interference or potentiation using population-level data has proven more difficult. Recent studies have quantified the prevalence of co-detections using populations drawn from clinical settings. Here, we focus on selection bias issues associated with this study design. We provide a quantitative account of the conditions under which selection bias arises in these studies, review previous attempts to address this bias, and propose unbiased study designs with sample size estimates needed to ascertain viral interference. We show that selection bias is expected in cross-sectional co-detection prevalence studies conducted in clinical settings, except under a strict set of assumptions regarding the relative probabilities of being included in a study limited to individuals with clinical disease under different viral states. Population-wide studies that collect samples from participants irrespective of their clinical status would meanwhile require large sample sizes to be sufficiently powered to detect viral interference, suggesting that a study's timing, inclusion criteria, and the expected magnitude of interference are instrumental in determining feasibility.

Pharmacokinetics and Safety of Firsocostat, an Acetyl-Coenzyme A Carboxylase Inhibitor, in Participants with Mild, Moderate, and Severe Hepatic Impairment.

Firsocostat is an oral, liver-targeted inhibitor of acetyl-coenzyme A carboxylase in development for the treatment of metabolic dysfunction-associated steatohepatitis. Hepatic organic anion transporting polypeptides play a significant role in the disposition of firsocostat with minimal contributions from uridine diphospho-glucuronosyltransferase and cytochrome P450 3A enzymes. This phase 1 study evaluated the pharmacokinetics and safety of firsocostat in participants with mild, moderate, or severe hepatic impairment. Participants with stable mild, moderate, or severe hepatic impairment (Child-Pugh A, B, or C, respectively [n = 10 per cohort]) and healthy matched controls with normal hepatic function (n = 10 per cohort) received a single oral dose of firsocostat (20 mg for mild and moderate hepatic impairment; 5 mg for severe hepatic impairment) with intensive pharmacokinetic sampling over 96 h. Safety was monitored throughout the study. Firsocostat plasma exposure (AUCinf) was 83%, 8.7-fold, and 30-fold higher in participants with mild, moderate, and severe hepatic impairment, respectively, relative to matched controls. Firsocostat was generally well tolerated, and all reported adverse events were mild in nature. Dose adjustment is not necessary for the administration of firsocostat in patients with mild hepatic impairment. However, based on the observed increases in firsocostat exposure, dose adjustment should be considered for patients with moderate or severe hepatic impairment, and additional safety and efficacy data from future clinical trials will further inform dose adjustment.

ALPINE2: Efficacy and safety of 14-day vs 28-day inhaled aztreonam for Pa eradication in children with cystic fibrosis.

BACKGROUND: Antibiotic eradication therapies recommended for newly isolated Pseudomonas aeruginosa (Pa) in people with cystic fibrosis (pwCF) can be burdensome. ALPINE2 compared the efficacy and safety of a shortened 14-day course of aztreonam for inhalation solution (AZLI) with 28-day AZLI in paediatric pwCF. METHODS: ALPINE2 (a double-blind, phase 3b study) included children aged 3 months to <18 years with CF and new-onset Pa infection. Participants were randomized to receive 75 mg AZLI three times daily for either 28 or 14 days followed by 14 days' matched placebo. The primary endpoint was rate of primary Pa eradication (no Pa detected during the 4 weeks post AZLI treatment). Non-inferiority was achieved if the lower 95% CI bound of the treatment difference between the two arms was above -20%. Secondary endpoints included assessments of Pa recurrence during 108 weeks of follow-up after primary eradication. Safety endpoints included treatment-emergent adverse events (TEAEs). RESULTS: In total, 149 participants were randomized (14-day AZLI, n = 74; 28-day AZLI, n = 75) and 142 (95.3%) completed treatment. Median age: 6.0 years (range: 0.3-17.0). Baseline characteristics were similar between treatment arms. Primary Pa eradication rates: 14-day AZLI, 55.9%; 28-day AZLI, 63.4%; treatment difference (CI), -8.0% (-24.6, 8.6%). Pa recurrence rates at follow-up end: 14-day AZLI, 54.1% (n = 20/37); 28-day AZLI, 41.9% (n = 18/43). TEAEs were similar between treatment arms. No new safety signals were observed. CONCLUSIONS: Non-inferiority of 14-day AZLI versus 28-day AZLI was not demonstrated. Both courses were well tolerated, further supporting AZLI short-term safety in paediatric and adolescent pwCF. CLINICALTRIALS: GOV: NCT03219164.

Challenges and Opportunities for Commercializing Technologies in the Pulmonary Arena: An Official American Thoracic Society Report.

"Translational medicine" has been a buzzword for over two decades. The concept was intended to be lofty, to reflect a new "bench-to-bedside" approach to basic and clinical research that would bridge fields, close gaps, accelerate innovation, and shorten the time and effort it takes to bring novel technologies from basic discovery to clinical application. Has this approach been successful and lived up to its promise? Despite incredible scientific advances and innovations developed within academia, successful clinical translation into real-world solutions has been difficult. This has been particularly challenging within the pulmonary field, because there have been fewer U.S. Food and Drug Administration-approved drugs and higher failure rates for pulmonary therapies than with other common disease areas. The American Thoracic Society convened a working group with the goal of identifying major challenges related to the commercialization of technologies within the pulmonary space and opportunities to enhance this process. A survey was developed and administered to 164 participants within the pulmonary arena. This report provides a summary of these survey results. Importantly, this report identifies a number of poorly recognized challenges that exist in pulmonary academic settings, which likely contribute to diminished efficiency of commercialization efforts, ultimately hindering the rate of successful clinical translation. Because many innovations are initially developed in academic settings, this is a global public health issue that impacts the entire American Thoracic Society community. This report also summarizes key resources and opportunities and provides recommendations to enhance successful commercialization of pulmonary technologies.

Derivation and validation of a noninvasive prediction tool to identify pulmonary hypertension in patients with IPF: Evolution of the model FORD.

BACKGROUND: The administration of inhaled prostanoids to patients with pulmonary hypertension (PH) related to idiopathic pulmonary fibrosis (IPF) and other fibrotic lung diseases improves functional outcomes. Selection of patients with IPF at risk for concomitant PH to undergo right heart catheterization (RHC) remains challenging. We sought to develop a clinical prediction tool based on common noninvasive parameters to identify PH in patients with IPF. METHODS: A prediction model based on noninvasive parameters was derived from patients enrolled in the ARTEMIS-IPF randomized, placebo-controlled clinical trial. Predictor variables were tested for association with the presence of PH diagnosed based on RHC. The derived multivariable logistic regression model and associated point-score index were then externally validated in a real-world cohort of patients with IPF. RESULTS: Of the 481 patients included in the ARTEMIS-IPF study, 9.8% (N = 47) were diagnosed with PH related to IPF. Four variables were associated with PH and were included in the final model: forced vital capacity/diffusing capacity for carbon monoxide ratio (F), oxygen saturation nadir during 6-minute walk test (6MWT) (O), race (R), and distance ambulated during 6MWT (D). A model containing continuous predictors (FORD calculator) and a simple point-score system (FORD index) performed similarly well in the derivation cohort (area under the curve [AUC]: 0.75 and 0.75, respectively) and validation cohort (AUC: 0.69 and 0.69, respectively). CONCLUSIONS: The FORD models are simple, validated tools incorporating noninvasive parameters that can be applied to identify patients at risk of PH related to IPF who may benefit from invasive testing.

Viral interference during influenza A-SARS-CoV-2 coinfection of the human airway epithelium and reversal by oseltamivir.

To gain insight into interactions among respiratory viruses, we modeled influenza A virus (IAV) - SARS-CoV-2 coinfections using differentiated human airway epithelial cultures. Replicating IAV induced a more robust interferon response than SARS-CoV-2 and suppressed SARS-CoV-2 replication in both sequential and simultaneous infections, whereas SARS-CoV-2 did not enhance host cell defense during influenza infection or suppress IAV replication. Oseltamivir, an antiviral targeting influenza, reduced IAV replication during coinfection but also reduced the host antiviral response and restored SARS-CoV-2 replication. These results demonstrate how perturbations in one viral infection can impact its effect on a coinfecting virus.

Effect of Hepatic Impairment on the Pharmacokinetics and Pharmacodynamics of Cilofexor, a Selective Nonsteroidal Farnesoid X Receptor Agonist.

Cilofexor is a nonsteroidal farnesoid X receptor agonist in clinical development for treatment of nonalcoholic steatohepatitis. This work characterized the pharmacokinetics, pharmacodynamics, safety, and tolerability of cilofexor in participants with normal hepatic function or hepatic impairment (HI). Participants with stable mild, moderate, or severe HI (Child-Pugh [CP] A, B, or C, respectively, [n = 10/group]) and healthy matched controls with normal hepatic function received a single oral dose of cilofexor (30 mg for CP-A or B; 10 mg for CP-C) with a standardized meal. Overall, 56 participants received cilofexor and completed the study. Cilofexor area under the plasma concentration-time curve was 76%, 2.5-fold, and 6.3-fold higher in participants with mild, moderate, or severe HI, respectively, relative to the area under the plasma concentration-time curve in matched participants with normal hepatic function. Cilofexor unbound fraction was 38%, 2-fold, and 3.16-fold higher in participants with mild, moderate, and severe HI, respectively, relative to participants with normal hepatic function. Moderate correlations were identified between cilofexor exposure and CP score or laboratory tests components of CP score. Serum 7α-hydroxy-4-cholesten-3-one and plasma fibroblast growth factor 19 were similar in participants with mild, moderate, or severe HI and participants with normal hepatic function. Cilofexor was generally well tolerated; all cilofexor-related adverse events were mild in severity. Cilofexor can be administered to patients with mild HI without dose adjustment. Caution and dose modification are warranted when administering cilofexor to patients with moderate or severe HI.

AI-based histologic scoring enables automated and reproducible assessment of enrollment criteria and endpoints in NASH clinical trials.

Clinical trials in nonalcoholic steatohepatitis (NASH) require histologic scoring for assessment of inclusion criteria and endpoints. However, guidelines for scoring key features have led to variability in interpretation, impacting clinical trial outcomes. We developed an artificial intelligence (AI)-based measurement (AIM) tool for scoring NASH histology (AIM-NASH). AIM-NASH predictions for NASH Clinical Research Network (CRN) grades of necroinflammation and stages of fibrosis aligned with expert consensus scores and were reproducible. Continuous scores produced by AIM-NASH for key histological features of NASH correlated with mean pathologist scores and with noninvasive biomarkers and strongly predicted patient outcomes. In a retrospective analysis of the ATLAS trial, previously unmet pathological endpoints were met when scored by the AIM-NASH algorithm alone. Overall, these results suggest that AIM-NASH may assist pathologists in histologic review of NASH clinical trials, reducing inter-rater variability on trial outcomes and offering a more sensitive and reproducible measure of patient therapeutic response.

Effects of filgotinib on semen parameters and sex hormones in male patients with inflammatory diseases: results from the phase 2, randomised, double-blind, placebo-controlled MANTA and MANTA-RAy studies.

OBJECTIVES: The phase 2 MANTA and MANTA-RAy studies aimed to determine if the oral Janus kinase 1 preferential inhibitor filgotinib affects semen parameters and sex hormones in men with inflammatory diseases. METHODS: MANTA (NCT03201445) and MANTA-RAy (NCT03926195) included men (21-65 years) with active inflammatory bowel disease (IBD) and rheumatic diseases (rheumatoid arthritis, spondyloarthritis or psoriatic arthritis), respectively. Eligible participants had semen parameters in the normal range per the WHO definition. In each study, participants were randomised 1:1 to receive once-daily, double-blind filgotinib 200 mg or placebo for 13 weeks for pooled analysis of the primary endpoint (proportion of participants with a ≥50% decrease from baseline in sperm concentration at week 13). Participants who met the primary endpoint were monitored over an additional 52 weeks for 'reversibility'. Secondary endpoints included change from baseline to week 13 in: sperm concentration, total motility, normal morphology, total count and ejaculate volume. Sex hormones (luteinising hormone, follicle stimulating hormone, inhibin B and total testosterone) and reversibility were exploratory endpoints. RESULTS: Across both studies, 631 patients were screened, and 248 were randomised to filgotinib 200 mg or placebo. Baseline demographics and characteristics were similar within indications between treatment groups. Numerically similar proportions of filgotinib-treated versus placebo-treated patients met the primary endpoint (8/120 (6.7%) vs 10/120 (8.3%)), Δ-1.7% (95% CI -9.3% to 5.8%)). There were no clinically relevant changes from baseline to week 13 in semen parameters or sex hormones, or patterns of reversibility between treatment groups. Filgotinib was well tolerated, with no new safety events. CONCLUSIONS: Results suggest that once daily filgotinib 200 mg for 13 weeks has no measurable impact on semen parameters or sex hormones in men with active IBD or inflammatory rheumatic diseases.

Ziritaxestat, a Novel Autotaxin Inhibitor, and Lung Function in Idiopathic Pulmonary Fibrosis: The ISABELA 1 and 2 Randomized Clinical Trials.

Importance: There is a major need for effective, well-tolerated treatments for idiopathic pulmonary fibrosis (IPF). Objective: To assess the efficacy and safety of the autotaxin inhibitor ziritaxestat in patients with IPF. Design, Setting, and Participants: The 2 identically designed, phase 3, randomized clinical trials, ISABELA 1 and ISABELA 2, were conducted in Africa, Asia-Pacific region, Europe, Latin America, the Middle East, and North America (26 countries). A total of 1306 patients with IPF were randomized (525 patients at 106 sites in ISABELA 1 and 781 patients at 121 sites in ISABELA 2). Enrollment began in November 2018 in both trials and follow-up was completed early due to study termination on April 12, 2021, for ISABELA 1 and on March 30, 2021, for ISABELA 2. Interventions: Patients were randomized 1:1:1 to receive 600 mg of oral ziritaxestat, 200 mg of ziritaxestat, or placebo once daily in addition to local standard of care (pirfenidone, nintedanib, or neither) for at least 52 weeks. Main Outcomes and Measures: The primary outcome was the annual rate of decline for forced vital capacity (FVC) at week 52. The key secondary outcomes were disease progression, time to first respiratory-related hospitalization, and change from baseline in St George's Respiratory Questionnaire total score (range, 0 to 100; higher scores indicate poorer health-related quality of life). Results: At the time of study termination, 525 patients were randomized in ISABELA 1 and 781 patients in ISABELA 2 (mean age: 70.0 [SD, 7.2] years in ISABELA 1 and 69.8 [SD, 7.1] years in ISABELA 2; male: 82.4% and 81.2%, respectively). The trials were terminated early after an independent data and safety monitoring committee concluded that the benefit to risk profile of ziritaxestat no longer supported their continuation. Ziritaxestat did not improve the annual rate of FVC decline vs placebo in either study. In ISABELA 1, the least-squares mean annual rate of FVC decline was -124.6 mL (95% CI, -178.0 to -71.2 mL) with 600 mg of ziritaxestat vs -147.3 mL (95% CI, -199.8 to -94.7 mL) with placebo (between-group difference, 22.7 mL [95% CI, -52.3 to 97.6 mL]), and -173.9 mL (95% CI, -225.7 to -122.2 mL) with 200 mg of ziritaxestat (between-group difference vs placebo, -26.7 mL [95% CI, -100.5 to 47.1 mL]). In ISABELA 2, the least-squares mean annual rate of FVC decline was -173.8 mL (95% CI, -209.2 to -138.4 mL) with 600 mg of ziritaxestat vs -176.6 mL (95% CI, -211.4 to -141.8 mL) with placebo (between-group difference, 2.8 mL [95% CI, -46.9 to 52.4 mL]) and -174.9 mL (95% CI, -209.5 to -140.2 mL) with 200 mg of ziritaxestat (between-group difference vs placebo, 1.7 mL [95% CI, -47.4 to 50.8 mL]). There was no benefit with ziritaxestat vs placebo for the key secondary outcomes. In ISABELA 1, all-cause mortality was 8.0% with 600 mg of ziritaxestat, 4.6% with 200 mg of ziritaxestat, and 6.3% with placebo; in ISABELA 2, it was 9.3% with 600 mg of ziritaxestat, 8.5% with 200 mg of ziritaxestat, and 4.7% with placebo. Conclusions and Relevance: Ziritaxestat did not improve clinical outcomes compared with placebo in patients with IPF receiving standard of care treatment with pirfenidone or nintedanib or in those not receiving standard of care treatment. Trial Registration: ClinicalTrials.gov Identifiers: NCT03711162 and NCT03733444.

Evaluation of the Potential for Cytochrome P450 and Transporter-Mediated Drug-Drug Interactions for Cilofexor, a Selective Nonsteroidal Farnesoid X Receptor (FXR) Agonist.

BACKGROUND AND OBJECTIVE: Cilofexor is a selective farnesoid X receptor (FXR) agonist in development for the treatment of nonalcoholic steatohepatitis and primary sclerosing cholangitis. Our objective was to evaluate potential drug-drug interactions of cilofexor as a victim and as a perpetrator. METHODS: In this Phase 1 study, healthy adult participants (n = 18-24 per each of the 6 cohorts) were administered cilofexor in combination with either perpetrators or substrates of cytochrome P-450 (CYP) enzymes and drug transporters. RESULTS: In total, 131 participants completed the study. As a victim, cilofexor area under the curve (AUC) was 651%, 795%, and 175% when administered following single-dose cyclosporine (600 mg; organic anion transporting polypeptide [OATP]/P-glycoprotein [P-gp]/CYP3A inhibitor), single-dose rifampin (600 mg; OATP1B1/1B3 inhibitor), and multiple-dose gemfibrozil (600 mg twice daily [BID]; CYP2C8 inhibitor), respectively, compared with the administration of cilofexor alone. Cilofexor AUC was 33% when administered following multiple-dose rifampin (600 mg; OATP/CYP/P-gp inducer). Multiple-dose voriconazole (200 mg BID; CYP3A4 inhibitor) and grapefruit juice (16 ounces; intestinal OATP inhibitor) did not affect cilofexor exposure. As a perpetrator, multiple-dose cilofexor did not affect the exposure of midazolam (2 mg; CYP3A substrate), pravastatin (40 mg; OATP substrate), or dabigatran etexilate (75 mg; intestinal P-gp substrate), but atorvastatin (10 mg; OATP/CYP3A4 substrate) AUC was 139% compared with atorvastatin administered alone. CONCLUSION: Cilofexor may be coadministered with inhibitors of P-gp, CYP3A4, or CYP2C8 without the need for dose modification. Cilofexor may be coadministered with OATP, BCRP, P-gp, and/or CYP3A4 substrates-including statins-without dose modification. However, coadministration of cilofexor with strong hepatic OATP inhibitors, or with strong or moderate inducers of OATP/CYP2C8, is not recommended.

A randomized controlled trial of presatovir for respiratory syncytial virus after lung transplant.

BACKGROUND: Respiratory syncytial virus (RSV) infection in lung transplant recipients is associated with high morbidity. This study evaluated the RSV fusion inhibitor presatovir in RSV-infected lung transplant recipients. METHODS: In this international Phase 2b, randomized, double-blind, placebo-controlled trial (NCT02534350), adult lung transplant recipients with symptomatic confirmed RSV infection for ≤7 days received oral presatovir 200 mg on day 1 and 100 mg daily on days 2 to 14, or placebo (2:1), with follow-up through day 28. There were 2 coprimary endpoints: time-weighted average change in nasal RSV load from day 1 to 7, calculated from nasal swabs, in the full analysis set ([FAS]; all patients who received study drug and had quantifiable baseline nasal RSV load) and time-weighted average change in nasal RSV load from day 1 to 7 in the subset of patients with pretreatment symptom duration at the median or shorter of the FAS. Secondary endpoints were changes in respiratory infection symptoms assessed using the Influenza Patient-Reported Outcomes questionnaire and lung function measured by spirometry. RESULTS: Sixty-one patients were randomized, 40 received presatovir, 20 placebo, and 54 were included in efficacy analyses. Presatovir did not significantly improve the primary endpoint in the FAS (treatment difference [95% CI], 0.10 [-0.43, 0.63] log10 copies/ml; p = 0.72) or the shorter symptom-duration subgroup (-0.12 [-0.94, 0.69] log10 copies/ml; p = 0.76). Secondary endpoints were not different between presatovir and placebo groups. Presatovir was generally well tolerated. CONCLUSIONS: Presatovir treatment did not significantly improve change in nasal RSV load, symptoms, or lung function in lung transplant recipients.

Rhesus macaque Bcl-6/Bcl-xL B cell immortalization: Discovery of HIV-1 neutralizing antibodies from lymph node.

Many HIV-1 vaccines are designed to elicit neutralizing antibodies, and pre-clinical testing is often carried out in rhesus macaques (RMs). We have therefore adapted a method of B cell immortalization for use with RM B cells. In this system, RM B cells are activated with CD40 ligand and RM IL-21 before transduction with a retroviral vector encoding Bcl-6, Bcl-xL, and green fluorescent protein. Importantly, RM B cells from lymph nodes are more effectively immortalized by this method than B cells from PBMC, a difference not seen in humans. We suggest the discrepancy between these two tissues is due to increased expression of CD40 on RM lymph node B cells. Immortalized RM B cells expand long-term, undergo minimal somatic hypermutation, express surface B cell receptor, and secrete antibodies into culture. This allows for the identification of cells based on antigen specificity and/or functional assays. Here, we show the characterization of this system and its application for the isolation of HIV-1 neutralizing antibodies from a SHIV.CH505-infected animal, both with and without antigen probe. Taken together, we show that Bcl-6/xL immortalization is a valuable and flexible tool for antibody discovery in RMs, but with important distinctions from application of the system in human cells.

Counterintuitive effect of antiviral therapy on influenza A-SARS-CoV-2 coinfection due to viral interference.

The resurgence of influenza and continued circulation of SARS-CoV-2 raise the question of how these viruses interact in a co-exposed host. Here we studied virus-virus and host-virus interactions during influenza A virus (IAV) -SARS-CoV-2 coinfection using differentiated cultures of the human airway epithelium. Coexposure to IAV enhanced the tissue antiviral response during SARS-CoV-2 infection and suppressed SARS-CoV-2 replication. Oseltamivir, an antiviral targeting influenza, reduced IAV replication during coinfection but also reduced the antiviral response and paradoxically restored SARS-CoV-2 replication. These results highlight the importance of diagnosing coinfections and compel further study of how coinfections impact the outcome of antiviral therapy.

Effect of Renal Impairment on the Pharmacokinetics of Firsocostat, an Acetyl-Coenzyme A Carboxylase Inhibitor, and Cilofexor, a Selective Nonsteroidal Farnesoid X Receptor Agonist.

Firsocostat, a liver-targeted acetyl-coenzyme A carboxylase inhibitor, and cilofexor, a nonsteroidal farnesoid X receptor agonist, are being developed in combination for treatment of nonalcoholic steatohepatitis. This phase 1 study evaluated firsocostat and cilofexor pharmacokinetics and tolerability in participants with severe renal impairment (SRI) and healthy matched controls (HMCs). Ten participants with SRI (estimated glomerular filtration rate by Modification of Diet in Renal Disease <30 mL/min/1.73 m2 ), and 10 HMCs received single oral doses of firsocostat (20 mg) on day 1 and cilofexor (100 mg) on day 7 in a fasted state. Plasma concentrations of firsocostat (and nonactive metabolite GS-834773) and cilofexor (and nonactive metabolites GS-716070 and GS-1056756) were collected over 96 hours and quantified; plasma exposures (area under the concentration-time curve [AUC] and peak concentration [Cmax ]) and plasma protein binding were characterized. Firsocostat AUC was ≈40% higher in SRI versus HMC, while Cmax was 8% lower. Observed exposures of the firsocostat metabolite were ≈4.6-fold higher in SRI participants versus HMC. Exposures (AUC and Cmax ) of cilofexor and metabolites and percentages of protein binding of all analytes were similar between SRI and HMC groups. Treatment-emergent adverse events were generally mild and not considered related to study drug. A <50% increase in firsocostat exposure was observed among SRI participants but was deemed not clinically relevant. There was no apparent effect of SRI on cilofexor exposure. Based on this trial, firsocostat and cilofexor dosing are not expected to require modification in patients who are renally impaired.

Fibro-Scope V1.0.1: an artificial intelligence/neural network system for staging of nonalcoholic steatohepatitis.

BACKGROUND: Fibro-Scope is an artificial intelligence/neural network system to determine the fibrosis stage in nonalcoholic steatohepatitis (NASH) using 12 parameters of the patient: age, sex, height, weight, waist circumference (WC), platelet count, and the levels of aspartate and alanine aminotransferase, gamma-glutamyltransferase, cholesterol, triglycerides, and type IV collagen 7S. However, measurement of WC is unstable and often missing from patient databases. Herein, we created Fibro-Scope V1.0.1 that has the same detection power as its predecessor, without the need to consider WC. METHODS: To build a new AI diagnostic system available for the global needs, data from 764 patients with NASH and bridging fibrosis (STELLAR-3) or compensated cirrhosis (STELLAR-4) that participated in two phase III trials were added to the Japanese data. Finally, the data of a total of 898 patients in the training and of 300 patients in the validation studies were analyzed, respectively. RESULTS: The discrimination of F0-2 from F3,4 through Fibro-Scope V1.0.1 was characterized by a 99.8% sensitivity, a 99.6% specificity, a 99.8% positive predictive value, and a 99.6% negative predictive value in a training study with gray zone analysis; similar effectiveness was also revealed in the analysis without a gray zone. In the validation studies with and without gray zone analysis, high sensitivity and specificity were also identified. Fibro-Scope V1.0.1 exerted a diagnostic accuracy for F3,4 advanced fibrosis that was comparable to that of the original Fibro-Scope and delivered high (> 92%) sensitivity and specificity. CONCLUSION: Fibro-Scope V1.0.1 can accurately diagnose F3,4 fibrosis without the need of WC.

Pharmacokinetics, pharmacodynamics, safety and tolerability of cilofexor, a novel nonsteroidal Farnesoid X receptor agonist, in healthy volunteers.

Cilofexor is a nonsteroidal farnesoid X receptor (FXR) agonist being evaluated for treatment of nonalcoholic steatohepatitis (NASH) and primary sclerosing cholangitis (PSC). This work characterized the pharmacokinetics, pharmacodynamic, safety, and tolerability of cilofexor in healthy participants. Cilofexor single and multiple once-daily doses (10 to 300 mg fasting or fed and twice-daily doses [15 and 50 mg; fed]; tablet formulation) were evaluated. In each cohort, participants were randomized to active drug or placebo in a 4:1 ratio (planned n = 15/cohort). Multiple dosing was for 14 days. Pharmacokinetic and pharmacodynamic samples were collected and safety and tolerability were assessed. Overall, 120 participants were enrolled in the study and 118 participants received at least one dose of study drug. Cilofexor pharmacokinetics followed bi-exponential disposition and its exposure increased in a less-than-dose-proportional manner over the 10 to 300 mg dose range, with no significant accumulation with repeated dosing. Moderate-fat meal reduced cilofexor area under the plasma concentration versus time curve (AUC) by 21% to 45%. Cilofexor increased plasma levels of fibroblast growth factor19 (FGF19) and reduced the serum bile acid intermediate 7α-hydroxy-4-cholesten-3-one (C4) and bile acids in an exposure-dependent manner. Cilofexor doses >30 mg appeared to achieve the plateau of intestinal FXR activation. Cilofexor was generally well tolerated; all treatment-emergent adverse events (TEAEs) were mild or moderate in severity, with headache being the most frequently observed TEAE. The pharmacokinetics pharmacodynamic safety, and tolerability results from this study supported further evaluations, and informed dose selection, of cilofexor in phase II studies in patients with NASH and PSC.

Nasal host response-based screening for undiagnosed respiratory viruses: a pathogen surveillance and detection study.

BACKGROUND: Symptomatic patients who test negative for common viruses are an important possible source of unrecognised or emerging pathogens, but metagenomic sequencing of all samples is inefficient because of the low likelihood of finding a pathogen in any given sample. We aimed to determine whether nasopharyngeal CXCL10 screening could be used as a strategy to enrich for samples containing undiagnosed viruses. METHODS: In this pathogen surveillance and detection study, we measured CXCL10 concentrations from nasopharyngeal swabs from patients in the Yale New Haven health-care system, which had been tested at the Yale New Haven Hospital Clinical Virology Laboratory (New Haven, CT, USA). Patients who tested negative for a panel of respiratory viruses using multiplex PCR during Jan 23-29, 2017, or March 3-14, 2020, were included. We performed host and pathogen RNA sequencing (RNA-Seq) and analysis for viral reads on samples with CXCL10 higher than 1 ng/mL or CXCL10 testing and quantitative RT-PCR (RT-qPCR) for SARS-CoV-2. We used RNA-Seq and cytokine profiling to compare the host response to infection in samples that were virus positive (rhinovirus, seasonal coronavirus CoV-NL63, or SARS-CoV-2) and virus negative (controls). FINDINGS: During Jan 23-29, 2017, 359 samples were tested for ten viruses on the multiplex PCR respiratory virus panel (RVP). 251 (70%) were RVP negative. 60 (24%) of 251 samples had CXCL10 higher than 150 pg/mL and were identified for further analysis. 28 (47%) of 60 CXCL10-high samples were positive for seasonal coronaviruses. 223 (89%) of 251 samples were PCR negative for 15 viruses and, of these, CXCL10-based screening identified 32 (13%) samples for further analysis. Of these 32 samples, eight (25%) with CXCL10 concentrations higher than 1 ng/mL and sufficient RNA were selected for RNA-Seq. Microbial RNA analysis showed the presence of influenza C virus in one sample and revealed RNA reads from bacterial pathobionts in four (50%) of eight samples. Between March 3 and March 14, 2020, 375 (59%) of 641 samples tested negative for 15 viruses on the RVP. 32 (9%) of 375 samples had CXCL10 concentrations ranging from 100 pg/mL to 1000 pg/mL and four of those were positive for SARS-CoV-2. CXCL10 elevation was statistically significant, and a distinguishing feature was found in 28 (8%) of 375 SARS-CoV-2-negative samples versus all four SARS-CoV-2-positive samples (p=4·4 × 10-5). Transcriptomic signatures showed an interferon response in virus-positive samples and an additional neutrophil-high hyperinflammatory signature in samples with high amounts of bacterial pathobionts. The CXCL10 cutoff for detecting a virus was 166·5 pg/mL for optimal sensitivity and 1091·0 pg/mL for specificity using a clinic-ready automated microfluidics-based immunoassay. INTERPRETATION: These results confirm CXCL10 as a robust nasopharyngeal biomarker of viral respiratory infection and support host response-based screening followed by metagenomic sequencing of CXCL10-high samples as a practical approach to incorporate clinical samples into pathogen discovery and surveillance efforts. FUNDING: National Institutes of Health, the Hartwell Foundation, the Gruber Foundation, Fast Grants for COVID-19 research from the Mercatus Center, and the Huffman Family Donor Advised Fund.